1. Field of the Invention
The present invention relates to a display panel, and more particularly to a pixel structure of a liquid crystal display panel.
2. Description of Related Art
Currently, liquid crystal displays have been mostly developed towards high brightness, high contrast ratio, large display size and wide viewing angle. In order to increase the viewing angle of the LCDs, several wide-viewing-angle techniques have been proposed. The most popular LCDs with the wide-viewing-angle feature include, for example, multi-domain vertical alignment (MVA) LCDs, in-plane switching (IPS) LCDs, and fringe field switching (FFS) LCDs.
FIG. 1 is a top view of a conventional pixel structure applied to the MVA LCD. Referring to FIG. 1, a pixel structure 100 is disposed on a thin film transistor (TFT) array substrate, which includes a scan line 110, a data line 120, a TFT 130, a pixel electrode 140 and a plurality of protrusions 150. The TFT 130 includes a gate 132, a semiconductor layer 134, a source 136a, a drain 136b and a contact window 138. The gate 132 is electrically connected with the scan line 110, and the semiconductor layer 134 is disposed over the gate 132. The source 136a and the drain 136b are disposed on the semiconductor layer 134, and the source 136a is electrically connected with the data line 120.
The pixel electrode 140 is electrically connected with the drain 136b via the contact window 138. In addition, in order to arrange the liquid crystal molecules to arrange in an multi-domain vertically aligned manner, the protrusions 150 are disposed on the pixel electrode 140, and other protrusions (not shown) are disposed on an opposite color filter substrate (not shown). Therefore, with the protrusions 150 and the said other protrusions, the liquid crystal molecules disposed between the TFT array substrate and the color filter substrate tilt in multiple directions so as to achieve the effect of wide viewing angle.
The MVA LCD can increase the viewing angle. However, the light transmittance of the MVA LCD may vary corresponding to a gray-level gamma curve when the viewing angle is increased from 0 degree to 90 degrees. In brief, with viewing angles varied, image color tones and brightness distribution provided by the MVA LCD may be distorted to a greater extent.